My .50 BD XR shoots Powerbelts real well, the all lead 405gr in particular, never shot anything else in it. Shot several Precision Rifle sabots and one of their conicals in my Super XR .45, but Powerbelts shoot best in it also, all with T7. Best friend has a standard BD .50, he also shoots the 405gr PB, only with 2F Goex.
Tim